Method of manufacturing an AlGaInP light emitting device using auto-doping

Abstract

A semiconductor light emitting device has a light emitting layer forming portion formed on the substrate and having an n-type layer and a p-type layer to provide a light emitting layer. A window layer is formed on a surface side of the light emitting layer forming portion. The window layer is formed of AlyGal−yAs (0.6≦y≦0.8) auto-doped in a carrier concentration of 5×10 18 -3×10 19 cm −3 . The resulting semiconductor light emitting device is free of degradation in crystallinity due to p-type impurity doping, thereby provide a high light emitting efficiency and brightness without encountering device degradation or damage.

What is claimed is:  
     
       1. A method of manufacturing a semiconductor light emitting device, comprising the steps of: 
       (a) epitaxially growing an AlGaInP-based compound semiconductor layer on a semiconductor substrate by an MOCVD process to form a light emitting layer forming portion; and  
       (b) epitaxially growing a p-type window layer of Al y Ga 1−y As (0.6≦y≦0.8) to a carrier concentration of 5×10 18 -3×10 19  cm −3  on a surface of said light emitting layer forming portion while controlling temperature by an MOCVD process without introducing a dopant gas.  
     
     
       2. A method according to claim  1 , further including a step of growing a protecting layer of Al z Ga 1−z As (0.45≦z≦0.6, z<y) by decreasing a flow rate of trimethyl aluminum as a reacting gas containing Al after growing said window layer.